A couple follow up questions:
Is there any way to securely share sensitive data between the App Clip and full app? There isn't shared Keychain access, and though there can be a shared container, Making Data Available to the App Clip’s Corresponding App - https://developer.apple.com/documentation/app_clips/making_data_available_to_the_app_clip_s_corresponding_app says, "Never store sensitive user information, such as passwords, in a shared app container or user defaults." So it would seem this isn't a secure option.
Related: Can an App Clip create keys in the Secure Enclave? Can the full app access them?
My understanding is that an App Clip is deleted after 30 days. Is all data deleted, including what's in Keychain/Secure Enclave? For example, if an App Clip writes to Keychain, is deleted after 30 days, and is reinstalled, can it still access what it originally wrote to Keychain?
Thanks!